1. Field of the Invention
The present invention relates generally to an ultrasonic probe apparatus, an ultrasonic probe system, and an ultrasonic probe method for detecting the presence of structural and material flaws in a tubular. More particularly, the invention relates to an ultrasonic probe apparatus, an ultrasonic probe system, and an ultrasonic probe method for detecting structural and material flaws having various orientations relative to the axial axis of the tubular.
2. Description of the Related Art
Non-destructive ultrasonic test methods are commonly used in the inspection of tubulars for structural and material flaws, e.g., cracks in the tubular walls, unevenness in the thickness of the tubular walls, and delaminations and inclusions in the tubular walls. Single-element and multi-element ultrasonic probes have been used in the tests. The probes are physically oriented in different directions to detect flaws with different orientations, such as longitudinally-oriented flaws, transversely-oriented flaws, and obliquely-oriented flaws. Detection in multiple different orientations using a single ultrasonic probe requires mechanical adjustment of the tilt angle of the probe for each different orientation, which is costly and time-consuming. Recently, ultrasonic phased array technology was introduced into the field to allow flaw detection in multiple orientations. Since the ultrasonic beams from a phased array probe can be steered/tilted electronically rather than mechanically, this enables one using the phased array technology to detect flaws with various orientations in a much more efficient way. Moreover, in view of the fact that the multiple elements in a phased array are divided into different groups that can be activated in sequence to inspect different locations on the test piece, a phased array probe is capable of scanning a large inspection area without movement.
European Patent Publication No. EP 1918700 A1 discloses a method for detecting flaws in tubulars using a phased array probe. The method includes arranging the phased array probe to face a tubular test object. Selected transducers in the probe transmit and receive ultrasonic waves such that ultrasonic waves are transmitted in the tubular in a plurality of different propagation directions. Transmission and reception time shifts are used to control transmission and reception of ultrasonic waves by the probe. The ultrasonic testing condition is such that the respective external refraction angles (or internal refraction angles) of the ultrasonic wave in the plurality of propagation directions are approximately equivalent. The transducers are arranged in a matrix along an annular curved surface designed such that the aforementioned ultrasonic testing condition can be achieved.
In European Patent Publication No. EP 1918700 A1, the phased array is configured as a two-dimensional array, which is expensive and complex to control. At present, one-dimensional (1D) phased array is being mostly used for industrial applications. For a 1D phased array, despite the presence of the electronic steering, it is still necessary to partly perform physical tilting of the probe in order to detect flaws in all orientations. Certainly, being able to quickly and easily tilt the probe is crucial in practice and is addressed in this disclosure.